1. Field of the Invention
The present invention generally relates to a cassette loading device, and in particular to a cassette loading device for detachably loading a recording medium cassette to a data recording and/or reproducing apparatus where the cassette loading device has a dust protection mechanism for effectively preventing external dust from sticking to a surface of the recording medium. The cassette loading device is adapted to such as a video and/or audio magnetic tape cassette and/or optical recording medium cassette or the like having a dustproof cover member for protection from the external dust.
2. Description of the Prior Art
Generally, in a cassette loading device for loading a magnetic recording tape cassette or the like on a magnetic recording and/or reproducing apparatus, for example, such as a video and/or audio tape recorder, the tape cassette is provided with a dustproof lid member on one side face of the tape cassette for covering a tape pull-out opening formed therein through which a magnetic recording tape is pulled out and pulled in, and thereby the magnetic tape can be protected from being stuck with external dust or waste particles outside the cassette by closing the dustproof lid member covering over the tape pull-out opening when the recording and/or reproducing operation on the magnetic tape is not played.
In this conventional construction of the cassette loading device, when the tape cassette is loaded on the magnetic recording and/or reproducing apparatus using the cassette loading device, the cassette loading device first receives a cassette insertion detection signal indicating that the cassette is inserted to the magnetic recording and/or reproducing apparatus and then the tape cassette is carried to a predetermined play position for playing recording and/or reproduction in the apparatus. Then, the dustproof lid is opened to pull out the magnetic tape from the cassette to be abutted with a magnetic pick-up head for playing recording and/or reproduction.
When the tape cassette is unloaded from the magnetic recording and/or reproducing apparatus, a cassette pullout switch is turned on to generate a cassette pullout signal which is applied to the cassette loading device. Upon receipt of the cassette pullout signal, the magnetic tape drawn out from the tape cassette is pulled back and stored in the tape cassette to release the loading state of the magnetic tape. Thereafter, the dustproof lid of the tape cassette is closed and the tape cassette is taken out from the magnetic recording and/or reproducing apparatus.
In this conventional cassette loading device, however, after the tape cassette is inserted in the magnetic recording and/or reproducing apparatus and loaded thereon, the dustproof lid remains in its opened state with the magnetic tape pulled out from the cassette until the tape cassette is taken out from the magnetic recording and/or reproducing apparatus with receipt of the cassette pullout signal.
Accordingly, after a necessary recording and/or reproducing operation is ended on the magnetic tape pulled out of the tape cassette loaded in the magnetic recording and/or reproducing apparatus, even in a stage where an access to the magnetic tape is no more necessary, the dustproof lid of the tape cassette inserted in the apparatus remains in the opened state so long as the cassette pullout signal is not received. Therefore, if the tape cassette is left as it is inserted in the apparatus with the magnetic tape pulled out from the cassette, there arises a problem that the dust, which has intruded into the apparatus, sticks to the surface of the magnetic tape.
The present invention has been developed to solve this problem and has an essential object to provide an improved cassette loading device having a dust protection mechanism effectively preventing dust from sticking to a surface of a recording medium even when a recording medium cassette is left as it is inserted in a recording and/or reproducing apparatus.
In order to achieve the object mentioned above, the present invention provides a cassette loading device for removably loading a cassette having a recording medium accommodated therein to and from a recording and/or reproducing apparatus, the cassette loading device comprising: a dust protection mechanism having a dustprooflid member provided on the cassette, wherein the dustproof lid member is closed when an access to the recording medium is judged to be unnecessary even in the course of holding the cassette loaded in the recording and/or reproducing apparatus.
The cassette loading device further comprises: a cassette loading mechanism for carrying the cassette between a play position accessible to the recording medium and a cassette insertion position in the recording and/or reproducing apparatus while loading the recording medium and releasing the loading condition thereof, and a loading control mechanism for controlling the dust protection mechanism and the cassette loading mechanism, wherein the dust protection mechanism comprises a lid opening and closing member for opening and closing the dustproof lid member, and, upon insertion of the cassette into the apparatus, the loading control mechanism controls the cassette loading mechanism to move the cassette to an abutment position abutted to the lid opening and closing member with the dustproof lid member in a closed state and subsequently to move the cassette to the play position with the dustproof lid member being opened under the control of the loading control mechanism.
The loading control mechanism includes a loading position detecting unit for detecting a position of the cassette loaded in the recording and/or reproducing apparatus, and the loading control mechanism controls the movement of the cassette based on the detected position of the cassette.
The loading control mechanism further includes an access judging unit for judging necessity of accessing the recording medium.
When the access judging unit judges that the access to the recording medium is necessary, the loading control mechanism controls the cassette to be kept in the play position for accessing the recording medium, and when the access judging unit judges that the access to the recording medium is unnecessary, the loading control mechanism controls the cassette to store the recording medium therein and to move back the cassette to the abutment position abutted to the lid opening and closing member with the dustproof lid member closed.
By this arrangement, according to the cassette loading device of the present invention, even when the recording medium cassette is left in the state of being stored in the recording and/or reproducing apparatus, in the case where the access to the recording medium is judged to be unnecessary, the loading condition of the recording medium cassette is released so that the dustproof lid member is closed under the control of the loading control mechanism, and therefore the surface of the recording medium can be effectively prevented from being stuck with dust.